1. Field of the Invention
This invention relates to an instrument for discharging water from the mouth during a dental treatment, which is suitably used for always discharging the mixed water and saliva which is at a deep portion of the mouth during treatment of teeth.
2. Description of the Prior Art
During treatment of the teeth, means are needed to remove saliva, medical liquid, cold washing water for cooling the teeth and removing cutting and polishing material and debris from the affected areas. This water mixture would otherwise stay in the deep portion of the mouth and choke the patient. The water mixture also disturbs the dentist in his treatment and in addition inflicts discomfort on the patient who feels like the mixture is being force down his throat. The devices shown in FIGS. 1 and 2 are known for removing this water mixture from the mouth.
The device shown in FIG. 1 is called a saliva-discharge tube. The whole saliva-discharge tube 1 has an approximately U-shape, to which end is mounted a saliva-collection tube 2 provided with orifices 2a.
The device shown in FIG. 2 is called a water suction tube. The whole water suction tube 3 having a relatively large diameter has an approximately &lt;-shape, to which is mounted a water collection tube 4 formed from a soft rubber tube.
In the device shown in FIG. 1, since an aperture of the saliva discharge tube 1 is small, this will not obstruct the treatment of teeth. But, the tube 1 is weak in suction force and in addition, the saliva collection tube 2 is also small and the distance from the bent position of the U-shape to the saliva collection tube 2 is short. Therefore, the saliva collection tube 2 does not reach the deep portion in the mouth, which is extremely insufficient to discharge the mixed water.
In the device shown in FIG. 2, an assistant holds the water suction tube 3 during treatment of the teeth and places the water collection tube 4 at appropriate positions to collect the water mixture. Water cannot be completely discharged merely by the arrangement as just mentioned and the mixed water cannot be prevented from staying in the deep portion in the mouth. Therefore, the treatment has to be often discontinued so that the patient may discharge the liquid. Furthermore, if the water collection tube 4 is inserted into the deep portion in the mouth, the sharp sense at the deep portion of the mouth stimulates the patient who feels like vomiting. For this reason the tube 4 is not used near the deep portion of the patient's mouth.